Cyclization of aryl 3-aryl propynoates into 4-arylcoumarins catalyzed by cyclometalated Platinum(II) complexes
作者:Olesia Zaitceva、Valérie Bénéteau、Dmitry S. Ryabukhin、Ivan I. Eliseev、Mikhal A. Kinzhalov、Benoit Louis、Aleksander V. Vasilyev、Patrick Pale
DOI:10.1016/j.tet.2020.131029
日期:2020.4
Cyclometalated (ppy)PtII complexes (ppy = 2-phenylpyridinato-C2,N) catalyze the intramolecular cyclization of aryl propynoates to form coumarins and benzocoumarins. The complex [(ppy)PtCl(MeCN)] (5 mol %) was the most active and efficient catalyst for such reaction, especially in the presence of AgSbF6 (15 mol %) in 1,2-dichloroethane. With this catalytic system, a wide range of substituents and functional
环金属化(ppy)Pt II配合物(ppy = 2-苯基吡啶基-C 2,N)催化丙酸芳基酯的分子内环化反应,形成香豆素和苯并香豆素。配合物[(ppy)PtCl(MeCN)](5 mol%)是用于该反应的最活性和最有效的催化剂,尤其是在存在1,2-二氯乙烷的AgSbF 6(15 mol%)的情况下。通过这种催化体系,证明了广泛的取代基和官能团与环化过程兼容,从而导致了多种取代的香豆素和苯并香豆素(22个实例,占77–99%)